Marziyeh Ebrahimi; Banafshe Fardoost; Gholamali Moghaddam; Masoud Adibmoradi; Hossein Janmohammadi; Sadegh Alijani; abbas rafat; Arash Javanmard
Abstract
In ovo feeding is considered as a useful tool to overcome the growth limitations during embryonic growth and after hatching in domesticated poultry. Therefore, the purpose of the present study was to investigate the effect of different levels of DL- methionine on the morphology of small intestine in ...
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In ovo feeding is considered as a useful tool to overcome the growth limitations during embryonic growth and after hatching in domesticated poultry. Therefore, the purpose of the present study was to investigate the effect of different levels of DL- methionine on the morphology of small intestine in ROSS 308 broiler chicks. In this regard, the total number of 240 eggs from Ross 308 broiler breeder were used according to a completely randomized design (CRD) with 8 experimental groups and 30 eggs per each treatment. The experimental treatments included different levels of DL-methionine amino acid (0.19, 0.38, 0.57, 0.76, 0.95 and 1.14 %), along with a sham-control group (sterile water injection) and a control group (without injection) which were injected into the amniotic fluid on the 14th d of incubation. After hatching, the chicks were weighed and slaughtered to measure small intestine morphological characteristics. Results of the study indicated that in ovo feeding of DL-methionine had a significant effect (p<0.05) on hatchability, weight and relative weight of jejunum, small intestine weight, as well as crypt diameter (except for duodenum), villus height, crypt depth, villus height to crypt depth ratio, and villus thickness in duodenum, jejunum, and ileum. On the other hand, no effect of treatments (p>0.05) was observed on chick weight and weight and length indexes of duodenum and ileum. Based on the results of this study, the best morphological response was observed in 76% DL-methionine treatment.
M.A. Abbasi; S. Alijani
Abstract
In the current study, major gene segregation for body weight at 8 weeks of age (BW8), age at sexual maturity (ASM), average egg weight during 84 days of laying (EW) and number of eggs laid during egg production period (EN) traits were evaluated using data which was collected from Fars Native Breeding ...
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In the current study, major gene segregation for body weight at 8 weeks of age (BW8), age at sexual maturity (ASM), average egg weight during 84 days of laying (EW) and number of eggs laid during egg production period (EN) traits were evaluated using data which was collected from Fars Native Breeding Center. Cox Box transformation was applied for all traits except for EN. Major gene detection was achieved by using highest posterior density region for genetic variance of major gene in the population. Therefore, a Bayesian segregation analysis model including non-genetic effects (generation-hatch, sex as fixed and laying period as covariate) and genetic effects (polygenic and biallelic major gene locus as random and fixed ones, respectively) was fitted on the data. The marginal posterior distribution of the model parameters were obtained by Gibbs sampling using iBay software. Based on diagnostic tests for each trait, two large chains were considered. For each chain, the number of Gibbs samples, burn in, and thining interval were equal to 500000, 50000 and 50, respectively. The Bayesian segregation analysis revealed the evidence for major gene segregation for ASM. For other traits there were not the same results. It is also recommended that the laboratory methods should be applied to verify the present results as well as additional methods for major gene detection for variety of traits in the same population
Ali Mohammadi; Sadegh Alijani; Akbar Taghizadeh; Mehdi Buhloli
Abstract
In order to estimate the genetic parameters and comparison legendre polynomials for production traits of Iranian Holstein dairy cattle test-day records of first lactation cows for milk yield, fat yield, protein yield, fat percentage and protein percentage traits were used. These records collected from ...
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In order to estimate the genetic parameters and comparison legendre polynomials for production traits of Iranian Holstein dairy cattle test-day records of first lactation cows for milk yield, fat yield, protein yield, fat percentage and protein percentage traits were used. These records collected from 2006 to 2010, by the Animal Breeding center of Iran. The genetic parameters were estimated using REML algorithm by random regression model with legendre polynomials of order 3 to 5. According to the results, order 5 of legendre polynomials were proposed for fitting permanent environment and additive genetic effects for the milk yield, fat and protein percentages traits, and order 4 of legendre polynomials for the fat and protein yields. Residual variances were considered homogeneous over the lactation period. The Phenotypic variance of the considered traits during lactation was not constant and it was higher at the beginning and the end of lactation. Additionally, the estimated permanent environment variance was larger than genetic variances throughout the lactation. Estimates of heritability were found to be lowest during early lactation. The additive genetic correlation between lactation adjacent days were more than between distant test days. The genetic trend of milk yield was showed an increasing phase during the10 past years, while this genetic trend for fat and protein percentages declined
